1. Field of the Invention
The present invention relates to a communication terminal device such as a facsimile machine.
2. Description of the Related Art
In a conventional communication terminal device such as a facsimile machine, a recipient communication terminal device stores a communication speed for each transmitter communication terminal device, and communicates under an optimum communication speed with each transmitter communication terminal device.
For example, in one conventional communication device, when a detecting unit detects a caller ID from a caller ID notification service at facsimile reception, and the detected caller ID is stored in a storage unit, during a training process, a Network Control Unit (NCU) and a Modulator-Demodulator (MODEM) return a Failure To Train (FTT) signal until the communication speed shifts down to the optimum signal speed that is stored and associated with the detected caller ID, and returns a Confirmation to Receive (CFR) signal under the optimum signal speed. When the detected caller ID is not stored in the storage unit, the caller ID and the optimum signal speed determined from a result of the facsimile communication are associated and stored.
However, in this conventional communication device, even when the communication speed associated with the caller ID is retrieved from the storage unit, the communication speed may not be the optimum communication speed at that point of time. According to a state of a communication line during the communication, the communication device may receive image data of low quality.